The Land Transport Authority (LTA) has lodged a police report against a Carousell user offering to modify decals used by private-hire drivers so they can be removed.

The Carousell user, dd740, put up his listing on July 11, 10 days after the requirement to put up the decal kicked in, the Today newspaper reported on Wednesday.

For $30, dd740 offered to modify the decal so that it could be removed without showing signs of having been tampered with.

The 14cm by 10cm plastic decal display must be stuck on the front and rear windscreens of private-hire vehicles. It is tamper-evident and is supposed to show the word "void" if it has been removed and reattached.

dd740 claimed his modified decal would let drivers "remove and paste back easily" without showing "void". The post has since been taken down but the seller can still be found on the app. His other listings offer renovation services and fengshui consultation services.

LTA said failure to affix or display these decals, or any form of tampering with them are offences under the Road Traffic Act.